Structure of marine communities
What makes some communities to support a great diversity while others are dominated by one or few species?
What is the relative importance of deterministic and stochastic processes in the structure and succession of marine communities?
These are some of the questions we attempt to understand through field experimentation, using artificial substrate to develop experimental communities. Sessile communities are excellent models to test ecological theories because they are easy to manipulate and also due to the fast development in a short time interval.
Life-history of marine organisms
Marine organisms show a great plasticity in the way they invest in offspring production. This plasticity is subjected to natural selection and is a result of the interaction between the genotype and the environmental conditions at the habitat that the organisms are living.
In order to understand the mechanisms by which phenotypic plasticity takes place and the contribution of plastic characters to the evolutional processes, we submit clones to different environmental conditions and quantify the importance of such conditions (natural or anthropic) in the phenotype determination and in the fitness of sessile organisms as ascidians and bryozoans.
Morphological and functional diversity
Analyses that focus on the diversity of evolutionary lineages, life forms and phenotypic variation of organisms go beyond richness and species abundance. While the diversity of species and evolutionary lineages provide information about the colonization history and the occupation of specific habitats, the morphological diversity is particularly interesting because in many cases the shape is directly related to the function of the organisms in such habitats.
This relationship can be a reflex of the real existence of a causal connection between design and performance, which affects fitness. In this context, the ecomorphology can be defined as “the study of the functional and ecological consequences of biodiversity”. Besides, the “functional groups” may be more important than the common parameters used to describe communities and ecosystems, because they are directly related to their functioning.
The main goal of this research area is to study the relationship between morphological and functional/ecological diversity of organisms in an ecological and evolutionary context. We attempt to identify key-species, to understand their roles in natural systems and the factors that promote coexistence, even of phylogenetic related species.
Anthropic changes in the coastal area
For a long time the larger human populations are established at the coastal area or nearby, which make this transition area between land and marine environment one of the areas most affected by anthropic action.
Buildings such as harbors, marinas and breakwaters, and the modification promoted by these structures change the physical and biotic conditions of marine ecosystems, besides providing new substrate for sessile organisms. These alterations can affect trophic structure of both benthic and nektonic communities in these areas and also frequently enhance the chance of introduction of exotic species, causing important ecological and economic damages.
In order to understand and to propose actions to mitigate these impacts, we work with sessile and nektonic organisms as models, testing how we can improve our use and conservation of coastal areas.
